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My "on the cheap" CNC router build
- Thread starter scottyd
- Start date
First run with this thing... A very light cut in pine of a demo skull and crossbones... Not exactly monumental results, but it works.. kinda.. I haven't adjusted any of the bearing lashes or nut lashes so the machine is all pretty loose during this the noise it's making is coming from the acme rods. My camera skills are not exactly on point during this. 
Already time for upgrades, the driver board I got as part of package deal is nothing short of terrible. It has lots of poor reviews and its apparent why, it wont drive the steppers very well, is slow, misses steps, doesn't hold a setting... Its great for initial tinkering, but nothing accurate, so new ones will be ordered.
The 1/2" 10 tpi acme rod I bought from ZORO are all bent somehow or another and are CRAP, I'm not at all happy about it and being I have spent a few hours trying to straighten them with little luck puts the salt in the wounds. A few of the bends are down right ridiculous. I will replace it with 5 start rod purchased from a reputable vendor.
Already time for upgrades, the driver board I got as part of package deal is nothing short of terrible. It has lots of poor reviews and its apparent why, it wont drive the steppers very well, is slow, misses steps, doesn't hold a setting... Its great for initial tinkering, but nothing accurate, so new ones will be ordered.
The 1/2" 10 tpi acme rod I bought from ZORO are all bent somehow or another and are CRAP, I'm not at all happy about it and being I have spent a few hours trying to straighten them with little luck puts the salt in the wounds. A few of the bends are down right ridiculous. I will replace it with 5 start rod purchased from a reputable vendor.
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Yeah, the first thing I did was to replace the electronics. Get a proper controller that can handle large steppers at high voltages. Also monitor you power supply to make sure that it doesn't suffer under heavy loads. That could also lead to missed steps.
Why does it keep stopping all the time in the video? Doing proper routing like that will burn both the bits and workpiece in no time. (While I remember to tell you: If you are using Mach3, learn when and when no to use CV mode. I learned about that the hard way)
What are you using to send the pulse trains from the computer to the stepper controller? USB or Parallel port?
Why does it keep stopping all the time in the video? Doing proper routing like that will burn both the bits and workpiece in no time. (While I remember to tell you: If you are using Mach3, learn when and when no to use CV mode. I learned about that the hard way)
What are you using to send the pulse trains from the computer to the stepper controller? USB or Parallel port?
Wow. I'm happy to see some motion out of this, but that was painful to watch.
My brother and I have been using a CNC Vertical Machining center, which is actually designed for shaping metal, not wood.
Like @Smilodon, I am concerned about the pauses in travel. Sounds like you are on the right track with the driver card replacement. The bent ACME rods are frightening to me, I hope you can get some satisfaction from the seller. What good is a CNC machine if it is not precise?
You aren't at this stage yet, but my biggest concern about your wood frame is cutter deflection when you are making deep vertical or near vertical passes on your piece. I am unsure how critical this will be when shaping wood, but when working in metal any flex in the frame can translate to imperfect surfaces. I know that your first goal is to cut inlays, so depth is not a factor, but it won't be long before you want to cut bodies and necks. Flex will come into play then.
I am curious to see how much improvement the new card and rods will make. Hats off to you for doing this, I have no doubt that you will work the bugs out and make a nice little machine for yourself.
My brother and I have been using a CNC Vertical Machining center, which is actually designed for shaping metal, not wood.
Like @Smilodon, I am concerned about the pauses in travel. Sounds like you are on the right track with the driver card replacement. The bent ACME rods are frightening to me, I hope you can get some satisfaction from the seller. What good is a CNC machine if it is not precise?
You aren't at this stage yet, but my biggest concern about your wood frame is cutter deflection when you are making deep vertical or near vertical passes on your piece. I am unsure how critical this will be when shaping wood, but when working in metal any flex in the frame can translate to imperfect surfaces. I know that your first goal is to cut inlays, so depth is not a factor, but it won't be long before you want to cut bodies and necks. Flex will come into play then.
I am curious to see how much improvement the new card and rods will make. Hats off to you for doing this, I have no doubt that you will work the bugs out and make a nice little machine for yourself.
I believe that when it's stopping its reading code for the z axis, I disabled the z during this because I wasn't sure if it was going to send the bit through the table or not. I did this after it plunged that bit as deep as it would go, turns out I had to reverse the z. I've noticed that the sample code does some strange stuff also Plus my steps per inch count is off for this threaded rod.
There's some major problems with that controller. The package I bought had two of them. Not long after that video both the Z and A axis stopped working on that controller. The voltage from the power supply was right on 24v which is what's recommended. I replaced it with the second one another TB6560. I'm still not completely satisfied with it and I sure don't want to rely on it, but it's much much better. I'm going to purchase a Gecko G540 when the machine (if this one) is further along I've read really good things about it.
The computer is sending pulses through the parallel port, the driver has a break out board built in.
Yes, I'm very upset about the acme rods. Don't ever purchase from Zoro. It's just one of those things, they were a little cheaper so I went for it. The money isn't a big deal, its the time that went into it.. Oh well.. The rods look fine under normal inspection but when they're spinning on the machine it becomes apparent that they're not straight. They'd probably work great for a garage door.
I'm already to the point of finding where she's flexing. I made a few deeper cuts last night its mostly easy fixes in the gantry area.
Thx! Wanna trade!?!?
I couldn't do that to you. Mine is just one of those run of the mill store bought models. Yours is "custom".
Plus, maybe someone should have mentioned this to you earlier, I only found out about it reading a few threads here on TB (not in the LC), but once you start using a cnc you are no longer a luthier. 
The LC crowd seems pretty accepting though, hopefully they won't kick us out.
The LC crowd seems pretty accepting though, hopefully they won't kick us out.Ah, yeah, that explains a lot. Having to reverse axes is fairly normal. Mach3 have a function for setting the steps per inch. You coul calculate it as well if you know the inclination if your screws and steps per rotation of your motor.
Did you measure the power supply while the machine is running. That's the critical measurement. The idle voltage isn't that important since most stepper systems handle a wide variance in voltage.
IIRC the stepper drivers I had was also TB6560-based. They are useless. I upgraded to a G540. That have been flawless. Just don't be surprised if your steppers are noisy while in idle when using a G540. IIRC the G540 also supports higher voltages which may help if you want to upgrade your powersupply in the future.
Good. One less thing to worry about.
Plus, maybe someone should have mentioned this to you earlier, I only found out about it reading a few threads here on TB (not in the LC), but once you start using a cnc you are no longer a luthier.
I see.... I was hoping to avoid that by luthiering my own cnc. Like a loophole or something.. It does have a few pieces of birds eye maple for gussets and what not. I should have laminated more things.
Honestly, I don't know that I ever was a luthier because I have never built a violin or a lute.. yes.. I read that unless you've built a violin you can not be considered a luthier.
And unless you machine metal you can not be a machinist.. We are in a gray area here for sure!
Ah, yeah, that explains a lot. Having to reverse axes is fairly normal. Mach3 have a function for setting the steps per inch. You coul calculate it as well if you know the inclination if your screws and steps per rotation of your motor.
Did you measure the power supply while the machine is running. That's the critical measurement. The idle voltage isn't that important since most stepper systems handle a wide variance in voltage.
IIRC the stepper drivers I had was also TB6560-based. They are useless. I upgraded to a G540. That have been flawless. Just don't be surprised if your steppers are noisy while in idle when using a G540. IIRC the G540 also supports higher voltages which may help if you want to upgrade your powersupply in the future.
Good. One less thing to worry about.
I didn't think to measure it while running.. very good point. I plan on spending a good part of today learning the Mach3 software.
Hopkins
Commercial User
Plus, maybe someone should have mentioned this to you earlier, I only found out about it reading a few threads here on TB (not in the LC), but once you start using a cnc you are no longer a luthier.
I'm guessing this was in the sub forum at the top of the list. There is a reason I avoid it like it was infested with plague.
I think they think that a CNC is a magical machine that takes a piece of wood and turns it into a bass without any human involvement. They don't realize that it only saves a little time on the front end of the process and that it only produces rough cut parts that still need alot of fine tuning before they are ready for finishing, which is alot of work in and of itself. People are idiots
It does have a few pieces of birds eye maple for gussets and what not. I should have laminated more things.
LMAO! I'll bet if you can find a place for some wenge or cocobolo they will give you your luthier card back
Strike two for me!
Lots of good stuff there Hopkins! It took a bunch of years of building to realize that even after completely finishing the basic construction of an instrument (I mean everything including inlay, frets, binding, etc.) and it looked 90% done it was really only 50% done.
I'm pretty happy with how this has gone so far. Other than the crap rods and less than average motor driver my machine is coming together very nicely. I've started bracing up anything that was showing signs of flex and so far so good.
I've did a little cutting last night using what I have now and it's working and will work very well soon. I've got a Gecko G540 on the way.
I've did a little cutting last night using what I have now and it's working and will work very well soon. I've got a Gecko G540 on the way.
Funny, but i bet that most people who would be foolish enough to make a remark that using the aid of cnc makes some one less worthy of a luthiery term hasn't ever put forth the effort and time to build something themselves. I WISH i had this thing going before I cut the clef holes in my current walnut semi hollow single cut.
I wonder if using a motorized router makes me less Luthierarian? Yes.. I just made that word up... I wonder if making words up makes me less wordiarian?
I wonder if using a motorized router makes me less Luthierarian? Yes.. I just made that word up... I wonder if making words up makes me less wordiarian?
